1 /*
2  * Elan I2C/SMBus Touchpad driver
3  *
4  * Copyright (c) 2013 ELAN Microelectronics Corp.
5  *
6  * Author: 林政維 (Duson Lin) <dusonlin@emc.com.tw>
7  * Version: 1.5.7
8  *
9  * Based on cyapa driver:
10  * copyright (c) 2011-2012 Cypress Semiconductor, Inc.
11  * copyright (c) 2011-2012 Google, Inc.
12  *
13  * This program is free software; you can redistribute it and/or modify it
14  * under the terms of the GNU General Public License version 2 as published
15  * by the Free Software Foundation.
16  *
17  * Trademarks are the property of their respective owners.
18  */
19 
20 #include <linux/acpi.h>
21 #include <linux/delay.h>
22 #include <linux/device.h>
23 #include <linux/firmware.h>
24 #include <linux/i2c.h>
25 #include <linux/init.h>
26 #include <linux/input/mt.h>
27 #include <linux/interrupt.h>
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/input.h>
33 #include <linux/uaccess.h>
34 #include <linux/jiffies.h>
35 #include <linux/completion.h>
36 #include <linux/of.h>
37 #include <linux/regulator/consumer.h>
38 #include <asm/unaligned.h>
39 
40 #include "elan_i2c.h"
41 
42 #define DRIVER_NAME		"elan_i2c"
43 #define ELAN_DRIVER_VERSION	"1.5.7"
44 #define ETP_MAX_PRESSURE	255
45 #define ETP_FWIDTH_REDUCE	90
46 #define ETP_FINGER_WIDTH	15
47 #define ETP_RETRY_COUNT		3
48 
49 #define ETP_MAX_FINGERS		5
50 #define ETP_FINGER_DATA_LEN	5
51 #define ETP_REPORT_ID		0x5D
52 #define ETP_REPORT_ID_OFFSET	2
53 #define ETP_TOUCH_INFO_OFFSET	3
54 #define ETP_FINGER_DATA_OFFSET	4
55 #define ETP_HOVER_INFO_OFFSET	30
56 #define ETP_MAX_REPORT_LEN	34
57 
58 /* The main device structure */
59 struct elan_tp_data {
60 	struct i2c_client	*client;
61 	struct input_dev	*input;
62 	struct regulator	*vcc;
63 
64 	const struct elan_transport_ops *ops;
65 
66 	/* for fw update */
67 	struct completion	fw_completion;
68 	bool			in_fw_update;
69 
70 	struct mutex		sysfs_mutex;
71 
72 	unsigned int		max_x;
73 	unsigned int		max_y;
74 	unsigned int		width_x;
75 	unsigned int		width_y;
76 	unsigned int		x_res;
77 	unsigned int		y_res;
78 
79 	u8			product_id;
80 	u8			fw_version;
81 	u8			sm_version;
82 	u8			iap_version;
83 	u16			fw_checksum;
84 	int			pressure_adjustment;
85 	u8			mode;
86 
87 	bool			irq_wake;
88 
89 	u8			min_baseline;
90 	u8			max_baseline;
91 	bool			baseline_ready;
92 };
93 
94 static int elan_enable_power(struct elan_tp_data *data)
95 {
96 	int repeat = ETP_RETRY_COUNT;
97 	int error;
98 
99 	error = regulator_enable(data->vcc);
100 	if (error) {
101 		dev_err(&data->client->dev,
102 			"failed to enable regulator: %d\n", error);
103 		return error;
104 	}
105 
106 	do {
107 		error = data->ops->power_control(data->client, true);
108 		if (error >= 0)
109 			return 0;
110 
111 		msleep(30);
112 	} while (--repeat > 0);
113 
114 	dev_err(&data->client->dev, "failed to enable power: %d\n", error);
115 	return error;
116 }
117 
118 static int elan_disable_power(struct elan_tp_data *data)
119 {
120 	int repeat = ETP_RETRY_COUNT;
121 	int error;
122 
123 	do {
124 		error = data->ops->power_control(data->client, false);
125 		if (!error) {
126 			error = regulator_disable(data->vcc);
127 			if (error) {
128 				dev_err(&data->client->dev,
129 					"failed to disable regulator: %d\n",
130 					error);
131 				/* Attempt to power the chip back up */
132 				data->ops->power_control(data->client, true);
133 				break;
134 			}
135 
136 			return 0;
137 		}
138 
139 		msleep(30);
140 	} while (--repeat > 0);
141 
142 	dev_err(&data->client->dev, "failed to disable power: %d\n", error);
143 	return error;
144 }
145 
146 static int elan_sleep(struct elan_tp_data *data)
147 {
148 	int repeat = ETP_RETRY_COUNT;
149 	int error;
150 
151 	do {
152 		error = data->ops->sleep_control(data->client, true);
153 		if (!error)
154 			return 0;
155 
156 		msleep(30);
157 	} while (--repeat > 0);
158 
159 	return error;
160 }
161 
162 static int __elan_initialize(struct elan_tp_data *data)
163 {
164 	struct i2c_client *client = data->client;
165 	int error;
166 
167 	error = data->ops->initialize(client);
168 	if (error) {
169 		dev_err(&client->dev, "device initialize failed: %d\n", error);
170 		return error;
171 	}
172 
173 	data->mode |= ETP_ENABLE_ABS;
174 	error = data->ops->set_mode(client, data->mode);
175 	if (error) {
176 		dev_err(&client->dev,
177 			"failed to switch to absolute mode: %d\n", error);
178 		return error;
179 	}
180 
181 	error = data->ops->sleep_control(client, false);
182 	if (error) {
183 		dev_err(&client->dev,
184 			"failed to wake device up: %d\n", error);
185 		return error;
186 	}
187 
188 	return 0;
189 }
190 
191 static int elan_initialize(struct elan_tp_data *data)
192 {
193 	int repeat = ETP_RETRY_COUNT;
194 	int error;
195 
196 	do {
197 		error = __elan_initialize(data);
198 		if (!error)
199 			return 0;
200 
201 		msleep(30);
202 	} while (--repeat > 0);
203 
204 	return error;
205 }
206 
207 static int elan_query_device_info(struct elan_tp_data *data)
208 {
209 	int error;
210 
211 	error = data->ops->get_product_id(data->client, &data->product_id);
212 	if (error)
213 		return error;
214 
215 	error = data->ops->get_version(data->client, false, &data->fw_version);
216 	if (error)
217 		return error;
218 
219 	error = data->ops->get_checksum(data->client, false,
220 					&data->fw_checksum);
221 	if (error)
222 		return error;
223 
224 	error = data->ops->get_sm_version(data->client, &data->sm_version);
225 	if (error)
226 		return error;
227 
228 	error = data->ops->get_version(data->client, true, &data->iap_version);
229 	if (error)
230 		return error;
231 
232 	error = data->ops->get_pressure_adjustment(data->client,
233 						   &data->pressure_adjustment);
234 	if (error)
235 		return error;
236 
237 	return 0;
238 }
239 
240 static unsigned int elan_convert_resolution(u8 val)
241 {
242 	/*
243 	 * (value from firmware) * 10 + 790 = dpi
244 	 *
245 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
246 	 * point).
247 	 */
248 
249 	return ((int)(char)val * 10 + 790) * 10 / 254;
250 }
251 
252 static int elan_query_device_parameters(struct elan_tp_data *data)
253 {
254 	unsigned int x_traces, y_traces;
255 	u8 hw_x_res, hw_y_res;
256 	int error;
257 
258 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
259 	if (error)
260 		return error;
261 
262 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
263 	if (error)
264 		return error;
265 
266 	data->width_x = data->max_x / x_traces;
267 	data->width_y = data->max_y / y_traces;
268 
269 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
270 	if (error)
271 		return error;
272 
273 	data->x_res = elan_convert_resolution(hw_x_res);
274 	data->y_res = elan_convert_resolution(hw_y_res);
275 
276 	return 0;
277 }
278 
279 /*
280  **********************************************************
281  * IAP firmware updater related routines
282  **********************************************************
283  */
284 static int elan_write_fw_block(struct elan_tp_data *data,
285 			       const u8 *page, u16 checksum, int idx)
286 {
287 	int retry = ETP_RETRY_COUNT;
288 	int error;
289 
290 	do {
291 		error = data->ops->write_fw_block(data->client,
292 						  page, checksum, idx);
293 		if (!error)
294 			return 0;
295 
296 		dev_dbg(&data->client->dev,
297 			"IAP retrying page %d (error: %d)\n", idx, error);
298 	} while (--retry > 0);
299 
300 	return error;
301 }
302 
303 static int __elan_update_firmware(struct elan_tp_data *data,
304 				  const struct firmware *fw)
305 {
306 	struct i2c_client *client = data->client;
307 	struct device *dev = &client->dev;
308 	int i, j;
309 	int error;
310 	u16 iap_start_addr;
311 	u16 boot_page_count;
312 	u16 sw_checksum = 0, fw_checksum = 0;
313 
314 	error = data->ops->prepare_fw_update(client);
315 	if (error)
316 		return error;
317 
318 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
319 
320 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
321 	for (i = boot_page_count; i < ETP_FW_VAILDPAGE_COUNT; i++) {
322 		u16 checksum = 0;
323 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
324 
325 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
326 			checksum += ((page[j + 1] << 8) | page[j]);
327 
328 		error = elan_write_fw_block(data, page, checksum, i);
329 		if (error) {
330 			dev_err(dev, "write page %d fail: %d\n", i, error);
331 			return error;
332 		}
333 
334 		sw_checksum += checksum;
335 	}
336 
337 	/* Wait WDT reset and power on reset */
338 	msleep(600);
339 
340 	error = data->ops->finish_fw_update(client, &data->fw_completion);
341 	if (error)
342 		return error;
343 
344 	error = data->ops->get_checksum(client, true, &fw_checksum);
345 	if (error)
346 		return error;
347 
348 	if (sw_checksum != fw_checksum) {
349 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
350 			sw_checksum, fw_checksum);
351 		return -EIO;
352 	}
353 
354 	return 0;
355 }
356 
357 static int elan_update_firmware(struct elan_tp_data *data,
358 				const struct firmware *fw)
359 {
360 	struct i2c_client *client = data->client;
361 	int retval;
362 
363 	dev_dbg(&client->dev, "Starting firmware update....\n");
364 
365 	disable_irq(client->irq);
366 	data->in_fw_update = true;
367 
368 	retval = __elan_update_firmware(data, fw);
369 	if (retval) {
370 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
371 		data->ops->iap_reset(client);
372 	} else {
373 		/* Reinitialize TP after fw is updated */
374 		elan_initialize(data);
375 		elan_query_device_info(data);
376 	}
377 
378 	data->in_fw_update = false;
379 	enable_irq(client->irq);
380 
381 	return retval;
382 }
383 
384 /*
385  *******************************************************************
386  * SYSFS attributes
387  *******************************************************************
388  */
389 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
390 					   struct device_attribute *attr,
391 					   char *buf)
392 {
393 	struct i2c_client *client = to_i2c_client(dev);
394 	struct elan_tp_data *data = i2c_get_clientdata(client);
395 
396 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
397 }
398 
399 static ssize_t elan_sysfs_read_product_id(struct device *dev,
400 					 struct device_attribute *attr,
401 					 char *buf)
402 {
403 	struct i2c_client *client = to_i2c_client(dev);
404 	struct elan_tp_data *data = i2c_get_clientdata(client);
405 
406 	return sprintf(buf, "%d.0\n", data->product_id);
407 }
408 
409 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
410 				      struct device_attribute *attr,
411 				      char *buf)
412 {
413 	struct i2c_client *client = to_i2c_client(dev);
414 	struct elan_tp_data *data = i2c_get_clientdata(client);
415 
416 	return sprintf(buf, "%d.0\n", data->fw_version);
417 }
418 
419 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
420 				      struct device_attribute *attr,
421 				      char *buf)
422 {
423 	struct i2c_client *client = to_i2c_client(dev);
424 	struct elan_tp_data *data = i2c_get_clientdata(client);
425 
426 	return sprintf(buf, "%d.0\n", data->sm_version);
427 }
428 
429 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
430 				       struct device_attribute *attr,
431 				       char *buf)
432 {
433 	struct i2c_client *client = to_i2c_client(dev);
434 	struct elan_tp_data *data = i2c_get_clientdata(client);
435 
436 	return sprintf(buf, "%d.0\n", data->iap_version);
437 }
438 
439 static ssize_t elan_sysfs_update_fw(struct device *dev,
440 				    struct device_attribute *attr,
441 				    const char *buf, size_t count)
442 {
443 	struct elan_tp_data *data = dev_get_drvdata(dev);
444 	const struct firmware *fw;
445 	int error;
446 	const u8 *fw_signature;
447 	static const u8 signature[] = {0xAA, 0x55, 0xCC, 0x33, 0xFF, 0xFF};
448 
449 	error = request_firmware(&fw, ETP_FW_NAME, dev);
450 	if (error) {
451 		dev_err(dev, "cannot load firmware %s: %d\n",
452 			ETP_FW_NAME, error);
453 		return error;
454 	}
455 
456 	/* Firmware file must match signature data */
457 	fw_signature = &fw->data[ETP_FW_SIGNATURE_ADDRESS];
458 	if (memcmp(fw_signature, signature, sizeof(signature)) != 0) {
459 		dev_err(dev, "signature mismatch (expected %*ph, got %*ph)\n",
460 			(int)sizeof(signature), signature,
461 			(int)sizeof(signature), fw_signature);
462 		error = -EBADF;
463 		goto out_release_fw;
464 	}
465 
466 	error = mutex_lock_interruptible(&data->sysfs_mutex);
467 	if (error)
468 		goto out_release_fw;
469 
470 	error = elan_update_firmware(data, fw);
471 
472 	mutex_unlock(&data->sysfs_mutex);
473 
474 out_release_fw:
475 	release_firmware(fw);
476 	return error ?: count;
477 }
478 
479 static ssize_t calibrate_store(struct device *dev,
480 			       struct device_attribute *attr,
481 			       const char *buf, size_t count)
482 {
483 	struct i2c_client *client = to_i2c_client(dev);
484 	struct elan_tp_data *data = i2c_get_clientdata(client);
485 	int tries = 20;
486 	int retval;
487 	int error;
488 	u8 val[3];
489 
490 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
491 	if (retval)
492 		return retval;
493 
494 	disable_irq(client->irq);
495 
496 	data->mode |= ETP_ENABLE_CALIBRATE;
497 	retval = data->ops->set_mode(client, data->mode);
498 	if (retval) {
499 		dev_err(dev, "failed to enable calibration mode: %d\n",
500 			retval);
501 		goto out;
502 	}
503 
504 	retval = data->ops->calibrate(client);
505 	if (retval) {
506 		dev_err(dev, "failed to start calibration: %d\n",
507 			retval);
508 		goto out_disable_calibrate;
509 	}
510 
511 	val[0] = 0xff;
512 	do {
513 		/* Wait 250ms before checking if calibration has completed. */
514 		msleep(250);
515 
516 		retval = data->ops->calibrate_result(client, val);
517 		if (retval)
518 			dev_err(dev, "failed to check calibration result: %d\n",
519 				retval);
520 		else if (val[0] == 0)
521 			break; /* calibration done */
522 
523 	} while (--tries);
524 
525 	if (tries == 0) {
526 		dev_err(dev, "failed to calibrate. Timeout.\n");
527 		retval = -ETIMEDOUT;
528 	}
529 
530 out_disable_calibrate:
531 	data->mode &= ~ETP_ENABLE_CALIBRATE;
532 	error = data->ops->set_mode(data->client, data->mode);
533 	if (error) {
534 		dev_err(dev, "failed to disable calibration mode: %d\n",
535 			error);
536 		if (!retval)
537 			retval = error;
538 	}
539 out:
540 	enable_irq(client->irq);
541 	mutex_unlock(&data->sysfs_mutex);
542 	return retval ?: count;
543 }
544 
545 static ssize_t elan_sysfs_read_mode(struct device *dev,
546 				    struct device_attribute *attr,
547 				    char *buf)
548 {
549 	struct i2c_client *client = to_i2c_client(dev);
550 	struct elan_tp_data *data = i2c_get_clientdata(client);
551 	int error;
552 	enum tp_mode mode;
553 
554 	error = mutex_lock_interruptible(&data->sysfs_mutex);
555 	if (error)
556 		return error;
557 
558 	error = data->ops->iap_get_mode(data->client, &mode);
559 
560 	mutex_unlock(&data->sysfs_mutex);
561 
562 	if (error)
563 		return error;
564 
565 	return sprintf(buf, "%d\n", (int)mode);
566 }
567 
568 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
569 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
570 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
571 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
572 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
573 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
574 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
575 
576 static DEVICE_ATTR_WO(calibrate);
577 
578 static struct attribute *elan_sysfs_entries[] = {
579 	&dev_attr_product_id.attr,
580 	&dev_attr_firmware_version.attr,
581 	&dev_attr_sample_version.attr,
582 	&dev_attr_iap_version.attr,
583 	&dev_attr_fw_checksum.attr,
584 	&dev_attr_calibrate.attr,
585 	&dev_attr_mode.attr,
586 	&dev_attr_update_fw.attr,
587 	NULL,
588 };
589 
590 static const struct attribute_group elan_sysfs_group = {
591 	.attrs = elan_sysfs_entries,
592 };
593 
594 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
595 			     const char *buf, size_t count)
596 {
597 	struct i2c_client *client = to_i2c_client(dev);
598 	struct elan_tp_data *data = i2c_get_clientdata(client);
599 	int error;
600 	int retval;
601 
602 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
603 	if (retval)
604 		return retval;
605 
606 	disable_irq(client->irq);
607 
608 	data->baseline_ready = false;
609 
610 	data->mode |= ETP_ENABLE_CALIBRATE;
611 	retval = data->ops->set_mode(data->client, data->mode);
612 	if (retval) {
613 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
614 			retval);
615 		goto out;
616 	}
617 
618 	msleep(250);
619 
620 	retval = data->ops->get_baseline_data(data->client, true,
621 					      &data->max_baseline);
622 	if (retval) {
623 		dev_err(dev, "Failed to read max baseline form device: %d\n",
624 			retval);
625 		goto out_disable_calibrate;
626 	}
627 
628 	retval = data->ops->get_baseline_data(data->client, false,
629 					      &data->min_baseline);
630 	if (retval) {
631 		dev_err(dev, "Failed to read min baseline form device: %d\n",
632 			retval);
633 		goto out_disable_calibrate;
634 	}
635 
636 	data->baseline_ready = true;
637 
638 out_disable_calibrate:
639 	data->mode &= ~ETP_ENABLE_CALIBRATE;
640 	error = data->ops->set_mode(data->client, data->mode);
641 	if (error) {
642 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
643 			error);
644 		if (!retval)
645 			retval = error;
646 	}
647 out:
648 	enable_irq(client->irq);
649 	mutex_unlock(&data->sysfs_mutex);
650 	return retval ?: count;
651 }
652 
653 static ssize_t min_show(struct device *dev,
654 			struct device_attribute *attr, char *buf)
655 {
656 	struct i2c_client *client = to_i2c_client(dev);
657 	struct elan_tp_data *data = i2c_get_clientdata(client);
658 	int retval;
659 
660 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
661 	if (retval)
662 		return retval;
663 
664 	if (!data->baseline_ready) {
665 		retval = -ENODATA;
666 		goto out;
667 	}
668 
669 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
670 
671 out:
672 	mutex_unlock(&data->sysfs_mutex);
673 	return retval;
674 }
675 
676 static ssize_t max_show(struct device *dev,
677 			struct device_attribute *attr, char *buf)
678 {
679 	struct i2c_client *client = to_i2c_client(dev);
680 	struct elan_tp_data *data = i2c_get_clientdata(client);
681 	int retval;
682 
683 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
684 	if (retval)
685 		return retval;
686 
687 	if (!data->baseline_ready) {
688 		retval = -ENODATA;
689 		goto out;
690 	}
691 
692 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
693 
694 out:
695 	mutex_unlock(&data->sysfs_mutex);
696 	return retval;
697 }
698 
699 
700 static DEVICE_ATTR_WO(acquire);
701 static DEVICE_ATTR_RO(min);
702 static DEVICE_ATTR_RO(max);
703 
704 static struct attribute *elan_baseline_sysfs_entries[] = {
705 	&dev_attr_acquire.attr,
706 	&dev_attr_min.attr,
707 	&dev_attr_max.attr,
708 	NULL,
709 };
710 
711 static const struct attribute_group elan_baseline_sysfs_group = {
712 	.name = "baseline",
713 	.attrs = elan_baseline_sysfs_entries,
714 };
715 
716 static const struct attribute_group *elan_sysfs_groups[] = {
717 	&elan_sysfs_group,
718 	&elan_baseline_sysfs_group,
719 	NULL
720 };
721 
722 /*
723  ******************************************************************
724  * Elan isr functions
725  ******************************************************************
726  */
727 static void elan_report_contact(struct elan_tp_data *data,
728 				int contact_num, bool contact_valid,
729 				bool hover_event, u8 *finger_data)
730 {
731 	struct input_dev *input = data->input;
732 	unsigned int pos_x, pos_y;
733 	unsigned int pressure, mk_x, mk_y;
734 	unsigned int area_x, area_y, major, minor;
735 	unsigned int scaled_pressure;
736 
737 	if (contact_valid) {
738 		pos_x = ((finger_data[0] & 0xf0) << 4) |
739 						finger_data[1];
740 		pos_y = ((finger_data[0] & 0x0f) << 8) |
741 						finger_data[2];
742 		mk_x = (finger_data[3] & 0x0f);
743 		mk_y = (finger_data[3] >> 4);
744 		pressure = finger_data[4];
745 
746 		if (pos_x > data->max_x || pos_y > data->max_y) {
747 			dev_dbg(input->dev.parent,
748 				"[%d] x=%d y=%d over max (%d, %d)",
749 				contact_num, pos_x, pos_y,
750 				data->max_x, data->max_y);
751 			return;
752 		}
753 
754 		/*
755 		 * To avoid treating large finger as palm, let's reduce the
756 		 * width x and y per trace.
757 		 */
758 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
759 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
760 
761 		major = max(area_x, area_y);
762 		minor = min(area_x, area_y);
763 
764 		scaled_pressure = pressure + data->pressure_adjustment;
765 
766 		if (scaled_pressure > ETP_MAX_PRESSURE)
767 			scaled_pressure = ETP_MAX_PRESSURE;
768 
769 		input_mt_slot(input, contact_num);
770 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
771 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
772 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
773 		input_report_abs(input, ABS_MT_DISTANCE, hover_event);
774 		input_report_abs(input, ABS_MT_PRESSURE,
775 				 hover_event ? 0 : scaled_pressure);
776 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
777 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
778 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
779 	} else {
780 		input_mt_slot(input, contact_num);
781 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
782 	}
783 }
784 
785 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
786 {
787 	struct input_dev *input = data->input;
788 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
789 	int i;
790 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
791 	u8 hover_info = packet[ETP_HOVER_INFO_OFFSET];
792 	bool contact_valid, hover_event;
793 
794 	hover_event = hover_info & 0x40;
795 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
796 		contact_valid = tp_info & (1U << (3 + i));
797 		elan_report_contact(data, i, contact_valid, hover_event,
798 				    finger_data);
799 
800 		if (contact_valid)
801 			finger_data += ETP_FINGER_DATA_LEN;
802 	}
803 
804 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
805 	input_mt_report_pointer_emulation(input, true);
806 	input_sync(input);
807 }
808 
809 static irqreturn_t elan_isr(int irq, void *dev_id)
810 {
811 	struct elan_tp_data *data = dev_id;
812 	struct device *dev = &data->client->dev;
813 	int error;
814 	u8 report[ETP_MAX_REPORT_LEN];
815 
816 	/*
817 	 * When device is connected to i2c bus, when all IAP page writes
818 	 * complete, the driver will receive interrupt and must read
819 	 * 0000 to confirm that IAP is finished.
820 	*/
821 	if (data->in_fw_update) {
822 		complete(&data->fw_completion);
823 		goto out;
824 	}
825 
826 	error = data->ops->get_report(data->client, report);
827 	if (error)
828 		goto out;
829 
830 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
831 		dev_err(dev, "invalid report id data (%x)\n",
832 			report[ETP_REPORT_ID_OFFSET]);
833 	else
834 		elan_report_absolute(data, report);
835 
836 out:
837 	return IRQ_HANDLED;
838 }
839 
840 /*
841  ******************************************************************
842  * Elan initialization functions
843  ******************************************************************
844  */
845 static int elan_setup_input_device(struct elan_tp_data *data)
846 {
847 	struct device *dev = &data->client->dev;
848 	struct input_dev *input;
849 	unsigned int max_width = max(data->width_x, data->width_y);
850 	unsigned int min_width = min(data->width_x, data->width_y);
851 	int error;
852 
853 	input = devm_input_allocate_device(dev);
854 	if (!input)
855 		return -ENOMEM;
856 
857 	input->name = "Elan Touchpad";
858 	input->id.bustype = BUS_I2C;
859 	input_set_drvdata(input, data);
860 
861 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
862 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
863 	if (error) {
864 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
865 		return error;
866 	}
867 
868 	__set_bit(EV_ABS, input->evbit);
869 	__set_bit(INPUT_PROP_POINTER, input->propbit);
870 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
871 	__set_bit(BTN_LEFT, input->keybit);
872 
873 	/* Set up ST parameters */
874 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
875 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
876 	input_abs_set_res(input, ABS_X, data->x_res);
877 	input_abs_set_res(input, ABS_Y, data->y_res);
878 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
879 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
880 
881 	/* And MT parameters */
882 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
883 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
884 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
885 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
886 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
887 			     ETP_MAX_PRESSURE, 0, 0);
888 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
889 			     ETP_FINGER_WIDTH * max_width, 0, 0);
890 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
891 			     ETP_FINGER_WIDTH * min_width, 0, 0);
892 	input_set_abs_params(input, ABS_MT_DISTANCE, 0, 1, 0, 0);
893 
894 	data->input = input;
895 
896 	return 0;
897 }
898 
899 static void elan_disable_regulator(void *_data)
900 {
901 	struct elan_tp_data *data = _data;
902 
903 	regulator_disable(data->vcc);
904 }
905 
906 static void elan_remove_sysfs_groups(void *_data)
907 {
908 	struct elan_tp_data *data = _data;
909 
910 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
911 }
912 
913 static int elan_probe(struct i2c_client *client,
914 		      const struct i2c_device_id *dev_id)
915 {
916 	const struct elan_transport_ops *transport_ops;
917 	struct device *dev = &client->dev;
918 	struct elan_tp_data *data;
919 	unsigned long irqflags;
920 	int error;
921 
922 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
923 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
924 		transport_ops = &elan_i2c_ops;
925 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
926 		   i2c_check_functionality(client->adapter,
927 					   I2C_FUNC_SMBUS_BYTE_DATA |
928 						I2C_FUNC_SMBUS_BLOCK_DATA |
929 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
930 		transport_ops = &elan_smbus_ops;
931 	} else {
932 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
933 		return -EIO;
934 	}
935 
936 	data = devm_kzalloc(&client->dev, sizeof(struct elan_tp_data),
937 			    GFP_KERNEL);
938 	if (!data)
939 		return -ENOMEM;
940 
941 	i2c_set_clientdata(client, data);
942 
943 	data->ops = transport_ops;
944 	data->client = client;
945 	init_completion(&data->fw_completion);
946 	mutex_init(&data->sysfs_mutex);
947 
948 	data->vcc = devm_regulator_get(&client->dev, "vcc");
949 	if (IS_ERR(data->vcc)) {
950 		error = PTR_ERR(data->vcc);
951 		if (error != -EPROBE_DEFER)
952 			dev_err(&client->dev,
953 				"Failed to get 'vcc' regulator: %d\n",
954 				error);
955 		return error;
956 	}
957 
958 	error = regulator_enable(data->vcc);
959 	if (error) {
960 		dev_err(&client->dev,
961 			"Failed to enable regulator: %d\n", error);
962 		return error;
963 	}
964 
965 	error = devm_add_action(&client->dev,
966 				elan_disable_regulator, data);
967 	if (error) {
968 		regulator_disable(data->vcc);
969 		dev_err(&client->dev,
970 			"Failed to add disable regulator action: %d\n",
971 			error);
972 		return error;
973 	}
974 
975 	/* Initialize the touchpad. */
976 	error = elan_initialize(data);
977 	if (error)
978 		return error;
979 
980 	error = elan_query_device_info(data);
981 	if (error)
982 		return error;
983 
984 	error = elan_query_device_parameters(data);
985 	if (error)
986 		return error;
987 
988 	dev_dbg(&client->dev,
989 		"Elan Touchpad Information:\n"
990 		"    Module product ID:  0x%04x\n"
991 		"    Firmware Version:  0x%04x\n"
992 		"    Sample Version:  0x%04x\n"
993 		"    IAP Version:  0x%04x\n"
994 		"    Max ABS X,Y:   %d,%d\n"
995 		"    Width X,Y:   %d,%d\n"
996 		"    Resolution X,Y:   %d,%d (dots/mm)\n",
997 		data->product_id,
998 		data->fw_version,
999 		data->sm_version,
1000 		data->iap_version,
1001 		data->max_x, data->max_y,
1002 		data->width_x, data->width_y,
1003 		data->x_res, data->y_res);
1004 
1005 	/* Set up input device properties based on queried parameters. */
1006 	error = elan_setup_input_device(data);
1007 	if (error)
1008 		return error;
1009 
1010 	/*
1011 	 * Systems using device tree should set up interrupt via DTS,
1012 	 * the rest will use the default falling edge interrupts.
1013 	 */
1014 	irqflags = client->dev.of_node ? 0 : IRQF_TRIGGER_FALLING;
1015 
1016 	error = devm_request_threaded_irq(&client->dev, client->irq,
1017 					  NULL, elan_isr,
1018 					  irqflags | IRQF_ONESHOT,
1019 					  client->name, data);
1020 	if (error) {
1021 		dev_err(&client->dev, "cannot register irq=%d\n", client->irq);
1022 		return error;
1023 	}
1024 
1025 	error = sysfs_create_groups(&client->dev.kobj, elan_sysfs_groups);
1026 	if (error) {
1027 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1028 			error);
1029 		return error;
1030 	}
1031 
1032 	error = devm_add_action(&client->dev,
1033 				elan_remove_sysfs_groups, data);
1034 	if (error) {
1035 		elan_remove_sysfs_groups(data);
1036 		dev_err(&client->dev,
1037 			"Failed to add sysfs cleanup action: %d\n",
1038 			error);
1039 		return error;
1040 	}
1041 
1042 	error = input_register_device(data->input);
1043 	if (error) {
1044 		dev_err(&client->dev, "failed to register input device: %d\n",
1045 			error);
1046 		return error;
1047 	}
1048 
1049 	/*
1050 	 * Systems using device tree should set up wakeup via DTS,
1051 	 * the rest will configure device as wakeup source by default.
1052 	 */
1053 	if (!client->dev.of_node)
1054 		device_init_wakeup(&client->dev, true);
1055 
1056 	return 0;
1057 }
1058 
1059 static int __maybe_unused elan_suspend(struct device *dev)
1060 {
1061 	struct i2c_client *client = to_i2c_client(dev);
1062 	struct elan_tp_data *data = i2c_get_clientdata(client);
1063 	int ret;
1064 
1065 	/*
1066 	 * We are taking the mutex to make sure sysfs operations are
1067 	 * complete before we attempt to bring the device into low[er]
1068 	 * power mode.
1069 	 */
1070 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1071 	if (ret)
1072 		return ret;
1073 
1074 	disable_irq(client->irq);
1075 
1076 	if (device_may_wakeup(dev)) {
1077 		ret = elan_sleep(data);
1078 		/* Enable wake from IRQ */
1079 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1080 	} else {
1081 		ret = elan_disable_power(data);
1082 	}
1083 
1084 	mutex_unlock(&data->sysfs_mutex);
1085 	return ret;
1086 }
1087 
1088 static int __maybe_unused elan_resume(struct device *dev)
1089 {
1090 	struct i2c_client *client = to_i2c_client(dev);
1091 	struct elan_tp_data *data = i2c_get_clientdata(client);
1092 	int error;
1093 
1094 	if (device_may_wakeup(dev) && data->irq_wake) {
1095 		disable_irq_wake(client->irq);
1096 		data->irq_wake = false;
1097 	}
1098 
1099 	error = elan_enable_power(data);
1100 	if (error) {
1101 		dev_err(dev, "power up when resuming failed: %d\n", error);
1102 		goto err;
1103 	}
1104 
1105 	error = elan_initialize(data);
1106 	if (error)
1107 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1108 
1109 err:
1110 	enable_irq(data->client->irq);
1111 	return error;
1112 }
1113 
1114 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1115 
1116 static const struct i2c_device_id elan_id[] = {
1117 	{ DRIVER_NAME, 0 },
1118 	{ },
1119 };
1120 MODULE_DEVICE_TABLE(i2c, elan_id);
1121 
1122 #ifdef CONFIG_ACPI
1123 static const struct acpi_device_id elan_acpi_id[] = {
1124 	{ "ELAN0000", 0 },
1125 	{ }
1126 };
1127 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1128 #endif
1129 
1130 #ifdef CONFIG_OF
1131 static const struct of_device_id elan_of_match[] = {
1132 	{ .compatible = "elan,ekth3000" },
1133 	{ /* sentinel */ }
1134 };
1135 MODULE_DEVICE_TABLE(of, elan_of_match);
1136 #endif
1137 
1138 static struct i2c_driver elan_driver = {
1139 	.driver = {
1140 		.name	= DRIVER_NAME,
1141 		.owner	= THIS_MODULE,
1142 		.pm	= &elan_pm_ops,
1143 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1144 		.of_match_table = of_match_ptr(elan_of_match),
1145 	},
1146 	.probe		= elan_probe,
1147 	.id_table	= elan_id,
1148 };
1149 
1150 module_i2c_driver(elan_driver);
1151 
1152 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1153 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1154 MODULE_LICENSE("GPL");
1155 MODULE_VERSION(ELAN_DRIVER_VERSION);
1156